How to permanently delete your facebook account

Sometimes you might have felt bored of facebook and have wanted to delete your facebook account. But when you have tried to delete your account. In account settings, facebook asks only to deactivate your account so that you can retrieve your friends and contacts and post next time you think to use facebook. But in case we do not want to use facebook and want to delete each and every information that facebook has about us, then we can consider permanently deleting the account.